1.2: "it is essentially a slightly sugared variant of the lambda calculus" Should it be the simply-typed lambda calculus? Also, there should be a reference; a significant percentage of those reading this report will have never heard of the lambda calculus. "with a straightforward denotational semantics" Seems that it should be so. Has anyone actually ever done that? If so, reference. If not, qualify. 1.3: "Errors in Haskell are semantically equivalent to _|_. Technically, they are not distinguishable from nontermination, so the language includes no mechanism for detecting or acting upon errors. However, implementations will probably try to provide useful information about errors. See Section 3.1 [where error and undefined are described]." This paragraph has always been very unsatisfying, especially since the Report itself does in fact provide a way of catching some errors at least since Haskell 98. 41.1: "The fail method of the IO instance of the Monad class raises a userError" Should be the default fail method. Regards, Yitz